Displays, for example for monitors, need to be backlit when using liquid crystal displays, which themselves do not light up. This is normally done using cold cathode lamps or, within the realms of miniaturization and the production of flat screens, two-dimensional optical light guides. Two-dimensional optical light guides as luminous areas are usually made of glass and are supplied with light, for example by light emitting diodes (LEDs), at the side areas. Particularly from display and hence luminous area sizes having a screen diagonal with a length of 17″, the problem arises that homogeneous illumination of the entire area is not or barely possible. Particularly in the center of the display, the illumination is weaker than in the rest of the screen. In addition, with conventional production facilities for lighting apparatus, it is a complex matter to produce lighting apparatus in different sizes. The production of two-dimensional lighting apparatus is a further difficulty as size increases.